/*
** 2039.c
** 
** Made by (seakage2h)
** Login   <seakage2h@seakage2h-ubuntu>
** 
** Started on  Fri Oct  3 16:49:44 2008 seakage2h
** Last update Sun May 12 01:17:25 2002 Speed Blue
*/

/* #include "2039.h" */
#include <stdio.h>
#include <string.h>

int main()
{
     int col, row, len, i, j;
     char str[201];

     while(scanf("%d", &col)){
	  if (!col) break;
	  scanf("%s", str);
	  len = strlen(str);
	  row = len / col;
	  for(i = 0; i < col; i++)
	       for(j = 0; j < row; j++)
		    if (j % 2) /*  */
			 putchar(str[col - i - 1 + j*col]);
		    else putchar(str[i+j*col]);
	  putchar('\n');
     }
     return 0;
}

